Mask and container and manufacturing apparatus

ABSTRACT

The present invention provides a large mask with a high mask accuracy for conducting selective deposition on a substrate with a large surface area. In accordance with the present invention, the mask body is fixed in a fixing position disposed on a line passing through a thermal expansion center in the width of the mask frame. Further, in accordance with the present invention, the substrate and mask body are fixed and deposition is carried out by moving the deposition source in the X direction or Y direction. A method comprising moving the deposition source in the X direction or Y direction is suitable for deposition on large substrates.

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD TO WHICH THEINVENTION BELONGS

The present invention relates to a film forming apparatus employed forforming a film of a material capable of forming a film by deposition(referred to hereinbelow as a deposition material) and a productionapparatus comprising such a film forming apparatus. In particular, thepresent invention relates to a mask employed for deposition in which afilm is formed by evaporating a deposition material from a depositionsource provided opposite to a substrate, a container for accommodatingthe deposition material, and a production apparatus.

PRIOR ART

Light-emitting elements using organic compounds featuring smallthickness and weight, fast response, DC low-voltage drive, and the like,as light-emitting substances have been expected to find application inflat panel displays of the next generation. In particular, displaydevices in which light emitting elements are disposed as a matrix havebeen considered to be superior to the conventional liquid-crystaldisplays in that they have a wide viewing angle and excellentvisibility.

As for the light emission mechanism of light-emitting elements, it isthought that electrons introduced from a cathode and holes introducedfrom an anode recombinate in an organic compound layer at thelight-emitting center and form molecular excitons under the effect ofthe voltage applied to a pair of electrodes sandwiching a layercontaining the organic compound and energy is then released and light isemitted when the molecular excitons return to a ground state. Singletexcitation and triplet excitation are known as excited states and lightemission is considered to be possible via any excited state.

In light-emitting devices formed by arranging such light-emittingelements as a matrix, drive methods such as a passive matrix drive(simple matrix type) and active matrix drive (active matrix type) can beused. However, when the pixel density is increased, the active matrixtype, in which a switch is provided for each pixel (or 1 dot) isconsidered to be advantageous because a low-voltage drive is possible.

Further, a layer comprising an organic compound has a multilayerstructure, typically in the form of “hole transfer layer/light-emittinglayer/electron transfer layer”. EL materials forming an EL layer aregenerally classified into low-molecular (monomer) materials andhigh-molecular (polymer) materials, and low-molecular materials areemployed to form films in deposition apparatuses.

The conventional deposition apparatuses have a substrate disposed in asubstrate holder and comprise a crucible (or a deposition boat) havingan EL material, that is, a deposition material, introduced therein, ashutter preventing the sublimated EL material from rising, and a heaterfor heating the EL material located inside the crucible. The EL materialheated with the heater is sublimated and forms a film on the rotatingsubstrate. In order to conduct uniform film formation in this process,the distance between the substrate and the crucible is set to 1 m ormore.

With the conventional deposition apparatus or deposition method, when anEL layer was formed by deposition, almost the entire sublimated ELmaterial adhered to the inner walls, shutter, or adhesion-preventingshield (a protective sheet for preventing the deposition material fromadhering to the inner walls of the film forming chamber) of the filmforming chamber of the deposition apparatus. For this reason, theutilization efficiency of expensive EL materials In the formation of theEL layer was extremely low, about 1% or less, and the production cost oflight-emitting devices was extremely high.

Further, in the conventional deposition apparatuses, the spacing betweenthe substrate and the deposition source was set to 1 m or more in orderto obtain a uniform film. Further, a problem associated with substrateswith a large surface area is that the film thickness can easily becomenonuniform in the central zone and peripheral edges of the substrate.Moreover, because the deposition apparatus has a structure with arotating substrate, a limitation is placed on the deposition apparatusesdesigned for substrates with a large surface area.

In addition, if a substrate with a large surface area and a mask fordeposition are rotated together after being brought into intimatecontact with each other, there is a risk of the displacement occurringbetween the mask and the substrate. Further, if the substrate or mask isheated during deposition, then dimensions change due to thermalexpansion. As a result, the dimensional accuracy and positional accuracydecrease owing to the difference in thermal expansion coefficientbetween the mask and substrate.

With the foregoing in view, the applicant of the present application hassuggested a deposition apparatus (Patent Document 1, Patent Document 2)as means for resolving the aforementioned problems. [Patent Document 1]JP-A-2001-247959. [Patent Document 2] JP-A-2002-60926.

[Problems Addressed by the Invention]

The present invention provides a production apparatus equipped with adeposition apparatus, which is a production apparatus reducingproduction cost by increasing the utilization efficiency of EL materialsand having excellent uniformity and throughput of EL layer deposition.

Further, the present invention also provides a production apparatus forefficient deposition of EL materials on substrates with a large surfacearea such as 320 mm×400 mm, 370 mm×470 mm, 550 mm×650 mm, 600 mm×720 mm,680 mm×880 mm, 1000 mm×1200 mm, 1100 mm×1250 mm, and 1150 mm×1300 mm.Further, the present invention also provides a deposition apparatus forobtaining a uniform film thickness over the entire substrate surfaceeven on a substrate with a large surface area.

In addition, a large mask with a high mask accuracy is provided forconducting selective deposition on a substrate with a large surfacearea.

[Means to Resolve the Problems]

In accordance with the present invention, in order to resolve theabove-mentioned problems, a mask is fixed to the thermal expansioncenter in a frame. The fixing is conducted locally only to the thermalexpansion center with an adhesive that has high resistance totemperature variations. The thermal expansion center is determined bythe material, shape, outer periphery, and inner periphery of the frame.

Further, the mask body is formed from a material having the same thermallinear expansion coefficient as the substrate. Because, the mask body isalso caused to expand thermally following the expanded-state of thesubstrate, a deposition position accuracy can be maintained. Because theposition in which the mask is fixed is the thermal expansion center, thealignment position is not changed even when the frame thermally expandsunder heating in a certain temperature range and the outer periphery andinner periphery thereof change.

Further, in accordance with the present invention, the substrate andmask are fixed, without rotation, during deposition. A film is formed onthe substrate by moving the deposition source holder in the X direction,Y direction, or Z direction during deposition.

The constitution of the invention disclosed in the present specificationis

-   -   a thin-sheet mask having a pattern opening, characterized in        that    -   the mask is fixed to a frame in a stretched state and the mask        is adhesively bonded in a location coinciding with a line        passing through a thermal expansion center in the members of the        frame.

Another constitution of the invention is

-   -   a thin-sheet mask having a pattern opening, characterized in        that    -   the mask is fixed to a frame in a stretched state and the mask        is adhesively bonded in a location on the outside of a line        passing through a thermal expansion center in the members of the        frame, and    -   the frame is caused to expand by heating during deposition and        the mask maintains the stretched state.

If fixing is conducted on the outside of the thermal expansion center inthe frame, the mask body is stretched as the frame expands under heatingand the deflection can be prevented. Thus, tension of the mask can bemaintained by using thermal expansion of the frame. Deposition ispreferably carried out by conducting heating appropriate for thematerial that will be deposited, and the fixing position may be suitablydetermined so that the appropriate tension is applied to the mask atthis heating temperature.

Further, in each of the above-described constitutions, four corners ofthe frame may have a curvature. Further in each of the above-describedconstitutions, the mask is characterized in that it is adhesively bondedto the frame with an adhesive having heat resistance. The mask may bealso fixed to the frame by welding.

Yet another constitution of the present invention is

-   -   a container for accommodating a deposition material, which is        disposed in a deposition source of a deposition apparatus,        characterized in that    -   the cross section in a plane of the container has a rectangular        or square shape and the opening portion through which the        deposition material passes has a thin elongated shape.

A configuration may be also used in which the mounting angle of thedeposition source can be freely set to match the evaporation center witha point on the substrate into which deposition is to be made whenco-deposition is conducted. However, a certain spacing between the twodeposition sources is required to tilt each deposition source at theangle. Therefore, it is preferred that the container has a prismaticcolumnar shape, as shown in FIG. 10, and the evaporation center beadjusted in the direction of the opening of the container. The containeris composed of an upper part and a lower part. A plurality of upperparts with different angles at which the deposition material flies outfrom the opening may be prepared and an appropriate upper part may beselected. Because the spread of deposition differs depending on thedeposition material, two deposition sources having different upper partsmounted thereon may be prepared when co-deposition is conducted.

Yet another constitution of the present invention is

-   -   a production apparatus comprising a loading chamber, a        transportation chamber linked to the loading chamber, a        plurality of film forming chambers linked to the transportation        chamber, and a disposition chamber linked to the film forming        chambers, characterized in that    -   the plurality of film forming chambers comprise means for fixing        a substrate which is linked to an evacuation chamber for        evacuating the inside of the film forming chambers, a mask, a        frame for fixing the mask, alignment means for aligning the mask        and the substrate, one or two deposition sources, means for        moving the deposition sources inside the film forming chambers,        and means for heating the substrate, and    -   the end portion of the mask is adhesively bonded in a location        matching a line passing through a thermal expansion center in        the members of the frame.

Yet another constitution of the present invention is a productionapparatus comprising a loading chamber, a transportation chamber linkedto the loading chamber, a plurality of film forming chambers linked tothe transportation chamber, and a disposition chamber linked to the filmforming chambers, characterized in that

-   -   the plurality of film forming chambers comprise means for fixing        a substrate which is linked to an evacuation chamber for        evacuating the inside of the film forming chambers, a mask, a        frame for fixing the mask, alignment means for aligning the mask        and the substrates, one or two deposition sources, means for        moving the deposition sources inside the film forming chambers,        and means for heating the substrate, and    -   the cross section in a plane of the container for accommodating        a deposition material, which is disposed in the deposition        source, has a rectangular or square shape and the opening        portion has a thin elongated shape.

The above-described constitution is characterized in that, the containeris composed of an upper part and a lower part, and evaporation of thematerial from the deposition source is adjusted by the shape of theopening portion in the upper part of the container. Furthermore, amiddle lid having a plurality of orifices opened inside thereof may beprovided in addition to the upper part and lower part in the container.

Further, each of the above-described configurations is characterized inthat the aforementioned film forming chamber and disposition chambercomprise means capable of introducing a material gas or cleaning gas andlinked to the chamber for evacuating the inside of the chambers.

Further, each of the above-described configurations is characterized inthat the deposition source can be moved in the X direction, Y direction,or Z direction inside the film forming chamber.

Furthermore, each of the above-described configurations is characterizedin that a shutter for partitioning the inside of the film formingchamber and shielding the deposition on the substrate is provided in thefilm forming chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view and a cross-sectional view (Embodiment 1)illustrating the mask in accordance with the present invention.

FIG. 2 illustrates Embodiment 2.

FIG. 3 illustrates Embodiment 3.

FIG. 4 is a perspective view illustrating the mask in accordance withthe present invention (Embodiment 1).

FIG. 5 illustrates a multichamber production apparatus (Example 1).

FIG. 6 is a top view of the deposition apparatus (Example 2).

FIG. 7 illustrates the disposition chamber and transportation mode(Example 2).

FIG. 8 is a top view of the inside of the film forming chamber (WorkingExample 3).

FIG. 9 is a top view of the inside of the film forming chamber (Example3).

FIG. 10 illustrates the container in accordance with the presentinvention (Embodiment 4).

FIG. 11 illustrates the deposition apparatus in accordance with thepresent invention (Embodiment 4).

FIG. 12 illustrates the configuration of an active matrix EL displaydevice.

FIG. 13 illustrates an example of an electronic device.

FIG. 14 is a block diagram of an electronic device shown in Example 6.

FIG. 15 is a block diagram of a controller.

FIG. 16 illustrates the charging mode of an electronic device shown inExample 6.

PREFERRED EMBODIMENTS OF THE INVENTION

The preferred embodiments of the invention will be described below.

(Embodiment 1)

FIG. 1(A) is a perspective view of the mask in accordance with thepresent invention. A mask body 122 is fixed in a fixing position A124 adisposed on a line passing through a thermal expansion center 121 in thewidth of a mask frame 120. Further, it is preferred that an arm (notshown in the figure) for supporting the mask frame be also supported inthe fixing position A124 a inside the deposition chamber.

Further, FIG. 1(B) is a cross-sectional view illustrating how asubstrate 124 is carried during deposition. During deposition, thesubstrate 124, mask body 122, and mask frame 120 are aligned to a fixedposition, and the mask body is brought into intimate contact over theentire surface with the deposition surface of the substrate by amagnetic force created by a magnet (not shown in the figure) provided atthe rear surface of the substrate. In the example shown herein, fixingwas conducted with the magnet, but mechanical fixing also may beemployed. Further, an opening portion 123 is provided in the mask body,the deposition material that passed through the opening portion 123forms a film, and a pattern is formed on the substrate 124.

Further, in accordance with the present invention, the substrate 124 andmask body 122 are fixed and deposition is conducted by moving thedeposition source in the X direction or Y direction. A method involvingmoving the deposition source in the X direction or Y direction issuitable for deposition on large substrates.

In accordance with the present invention, a mask body using a materialhaving a thermal expansion coefficient identical to that of thesubstrate is preferably used. For example, when a glass substrate isused, a 42 Alloy (Fe—Ni alloy: Ni 42%) or 36 Invar (Fe—Ni alloy: Ni36%), which have a thermal expansion coefficient close to that of theglass, may be used for the mask body. Though the mask body and substrateare heated during deposition, because they expand to the same degree,hardly any displacement occurs. Further, the mask frame 120 is alsoheated, but because the position of the thermal expansion center does nochange, hardly any displacement occurs, even if the mask frame 120 andmask body 122 are from different material and have different thermalexpansion coefficients. The present invention is especially effectivefor deposition on large substrates in which displacement to easilycaused by heating.

Further, the mask may be formed by an etching method or electroformingmethod. Further, the mask may be also formed by combining an etchingmethod based on dry etching or wet etching with an electroforming methodcarried out in an electroforming tank of the same metal as that of thedeposition mask.

Further, because the tension of the mask body 122 is maintained in aheated state, if fixing is conducted in a fixing position B124 b locatedto the outer periphery from the thermal expansion center, instead of thefixing position A124 a, then the tension of the mask body 122 can bemaintained by using the expansion amount of the mask frame. The distancefrom the thermal expansion center to the fixing position B124 b may besuitably determined according to the heating temperature duringdeposition, thermal expansion coefficient of the frame, and outerperiphery and inner periphery of the frame.

Further, FIG. 1(C) illustrates an example in which four corners of themask frame were rounded. Rounding the four corners of the mask preventsthe corners of the mask frame is prevented from being damaged by anyimpacts. In FIG. 1(C), the reference numeral 130 stands for a maskframe, 131—a thermal expansion center, 132—a mask body, and 133—anopening portion.

Further, FIG. 4 shows an example in which a clearance is formed and aplay portion 223 b is provided in the four corners of the openingportion 223 a. Providing the play portion 223 b prevents cracks fromentering the mask body 232 from the corner of the adjacent openingportion even when a tension is applied to the mask body 232 and it isthermally expanded. Further, in FIG. 4, the reference numeral 230 standsfor a mask frame, 231—a thermal expansion center, 232—a mask body, and224—a fixing position.

(Embodiment 2)

Here, the configuration of substrate holding means will be described ingreater detail with reference to FIG. 2. When a substrate with a largesurface area is used and gang printing is carried out (a plurality ofpanels are formed from one substrate), substrate holding means isprovided to support the substrate so as to be in contact with theportions that will be scribe lines. Thus, a substrate is placed onsubstrate holding means and a deposition material is sublimated from thedeposition source holder provided below the substrate holding means anddeposited on the areas that are not in contact with the substrateholding means. As a result, the deflection of substrates with a largesurface area can be suppressed to 1 mm or less.

FIG. 2(A) is a perspective view showing a substrate holding means 301having a substrate 303 and a mask 302 placed thereon. FIG. 2(B) showsonly the substrate holding means 301.

Further, FIG. 2(C) shows a cross-sectional view of the substrate holdingmeans in which the substrate 303 was placed on the mask 302; thesubstrate holding means is composed of a metal sheet (typically, Ti or ashape memory alloy) with a height, h, of 10 mm-50 mm and a width 1 mm-5mm. Further, the substrate holding means may be also a wire composed ofa shape memory alloy. The substrate holding means is fixed to the mask302 by welding or adhesively. Further, the mask 302 is fixed with anadhesive material in a position serving as a thermal expansion center ofthe mask frame 304.

The substrate holding means 301 inhibits the deflection of the substrateor the deflection of the mask under the weight of the substrate.Further, the substrate holding means 301 can inhibit the deflection ofthe mask and maintain the tension of the mask.

The shape of the substrate holding means 301 is not limited to thatshown in FIG. 2(A)-FIG. 2(C) and is a shape which does not overlap theopening portion of the mask which is provided in the mask.

The present embodiment can be freely combined with Embodiment 1.

(Embodiment 3)

Here, an example of conducting the deposition of a RGB pattern is shown.

FIG. 3(A) is an exploded perspective view of a mask composed of a maskframe 420 and a mask body 422.

A thermal expansion center 421 of the mask frame 420 coincides with theadhesive bonding location 426 with the mask body 422. Further, the maskbody is provided with an opening portion 423. The opening portion 423 isprovided as a pattern of one kind among the RGB. Here, for the sake ofsimplicity, a mask having an opening portion with 9 rows×15 columns isshown, but it goes without saying that this shape is not limiting, andthe mask may correspond to the desired number of pixels, for example, to640×480 pixels of a VGA class or 1024×768 pixels of a XGA class.

Three masks are prepared for RGB patterning. When three masks areprepared, a common mask design is employed for the mask bodies, but whenthe masks are fixed to the mask frame, each mask is individuallyadhesively bonded to obtain the prescribed pixel position.Alternatively, the deposition may be conducted by employing one mask andshifting the mask with respect to the substrate for each RGB duringalignment. Further, the deposition may be also conducted by employingone mask and shifting the mask with respect to the substrate for eachRGB during alignment inside one chamber.

FIG. 3(B) is a perspective view of the substrate after the deposition ofthree kinds of RGB was conducted. A deposited film 431 for red color, adeposited film 432 for green color, and a deposited film 433 for bluecolor have been regularly deposited on the substrate 430. A patterncomprising a total of 405 (27 rows×15 columns) units has been formed.

This embodiment can be freely combined with Embodiment 1 or Embodiment2.

(Embodiment 4)

Here, a container for accommodating a deposition material is shown inFIG. 10. FIG. 10(A) is a perspective view of the container. FIG. 10(B)is a cross-sectional view obtained by cutting along the chain line A-B.FIG. 10(C) is a cross-sectional view obtained by cutting along the dotline C-D.

When the mounting angle of the deposition source is changed, acylindrical crucible and a heater surrounding the crucible are alsoinclined. Therefore, when co-deposition is carried out by using twocrucibles, the spacing therebetween is increased. If the spacing isincreased, two different deposition materials are difficult to mixhomogeneously. Furthermore, when it is desirable to conduct depositionwith a small gap between the deposition source and the substrate, then auniform film is difficult to obtain.

In accordance with the present invention, the evaporation center isadjusted with an opening B10 in the container upper part 800 a, ratherthan by changing the mounting angle of the deposition source. Thecontainer is composed of the container upper part 800 a, a containerlower part 800 b, and a middle lid 800 c. A plurality of small orificesare provided in the middle lid 800 c, and the deposition material passesthrough those orifices during deposition. Further, the container isformed of a material such as a BN sintered body, a BN and AlN compositesintered body, quartz glass, and graphite and can withstand hightemperature, high pressure, and low pressure. The deposition directionand spread differ depending on the deposition material. Therefore, thecontainer is appropriately prepared in which the surface area of theopening 810, the guide portion of the opening, and the position of theopening are adjusted according to each deposition material.

With the container in accordance with the present invention, thedeposition center can be adjusted without tilting the heater of thedeposition source. Further, as shown in FIG. 10(D), in co-deposition,the orientations of the opening 810 a and 810 b can be aligned, spacingbetween a plurality of containers accommodating a plurality of differentdeposition materials (materials A805, material B806) can be decreased,and deposition can be conducted, while homogeneously mixing thematerials. Referring to FIG. 10(D), heating means 801-804 are connectedto individual power sources and mutually independent temperature controlthereof is conducted. Furthermore, a uniform film can be obtained evenwhen it is desirable to conduct deposition with a spacing between thedeposition source and substrate decreased, for example, to 20 cm orless.

Further, an example different from that shown in FIG. 10(D) is shown inFIG. 10(E). In the example shown in FIG. 10(E), deposition is conductedby using an upper part with an opening 810 c provided for evaporation inthe vertical direction and by using an upper part having an opening 810d inclined according to this direction. In the configuration shown inFIG. 10(E), too, heating means 801, 803, 807, and 808 are connected toseparate power sources and mutually independent temperature controlthereof is conducted.

The container in accordance with the present invention shown in FIG. 10has a fine long opening. Therefore, the uniform deposition region isexpanded and the container is suitable for uniform deposition on a fixedsubstrate with a large surface area.

FIG. 11 is a top view of a film forming apparatus for conductingdeposition by using the container shown in FIG. 10 with a fixedsubstrate with a large surface area.

A substrate 815 is transported from a transportation chamber 813 into afilm forming chamber 812 through a shutter 814. If necessary, alignmentof the substrate and a mask (not shown in the figure) is conducted inthe transportation chamber 813 or film forming chamber 812.

The container 800 composed of the container upper portion 800 a havingthe opening 810 and the container lower portion 800 b is disposed in thedeposition source holder 811. The deposition source holder 811 is movedbelow the substrate 815 with movement means (not shown in the figure)that can move in the X direction, Y direction, or Z direction. A chainline in FIG. 11 shows an example of the movement path of the depositionsource holder.

In the deposition apparatus shown in FIG. 11, the clearance distance, d,between the substrate 813 and the deposition source holder 811 istypically decreased to 30 cm or less, preferably 20 cm or less, evenmore preferably 5 cm-15 cm, and the utilization efficiency of thedeposition material is greatly increased.

Further, there is a risk of the deposition mask (not shown in thefigure) being heated due to the decrease in the clearance distance, d,between the substrate 813 and the deposition source holder 811 typicallyto 30 cm or less, preferably to 5 cm-15 cm. Therefore, it is preferredthat a metal material (for example, a material such as a metal with ahigh melting point such as tungsten, tantalum, chromium, nickel, ormolybdenum or alloys containing such elements, stainless steel, Inconel,and Hastelloy) that has a low thermal expansion coefficient and highresistance to heat-induced deformation be used for the deposition mask14. An example of such a material is an alloy with low thermal expansionwhich contains nickel 42% and iron 58%. Further, a structure in which acooling medium (cooling water, cooling gas) is circulated to thedeposition mask for cooling the heated deposition mask may be alsoprovided.

This embodiment can be freely combined with any of Embodiments 1 to 3.

The present invention of the above-described constitution will beexplained in greater detail with the examples described hereinbelow.

EXAMPLES Example 1

FIG. 5 is a top view of the production apparatus of a multichamber type.In the production apparatus shown in FIG. 5, the chambers are disposedin the order of tasks performed.

In the production apparatus shown in FIG. 5, at least the transportationchambers 504 a, 504 b, 508, 514 are constantly maintained under vacuumand the film forming chambers 506W1, 506W2, 506W3 are constantlymaintained under vacuum. Therefore, the operations of evacuating thefilm forming chambers and the operations of filling the film formingchambers with nitrogen can be omitted and a film forming treatment canbe carried out continuously within a short time.

Deposited in one film forming chamber is only one layer of the EL layer(comprises a hole transfer layer, a hole injection layer, alight-emitting layer, an electron transfer layer, an electron injectionlayer, and the like) composed of a stack of layers composed of differentmaterials. A deposition source holder capable of moving inside a filmforming chamber is provided in each film forming chamber. A plurality ofsuch deposition source holders are prepared and a plurality ofcontainers (crucibles) having EL materials introduced therein areappropriately provided and disposed in the film forming chambers. Thesubstrate can be set in a face-down system, the position alignment ofthe deposition mask can be carried out with a CCD or the like, and filmformation can be selectively carried out by conducting the deposition bya resistance heating method.

The disposition of the containers (crucibles) having EL materialsintroduced therein, replacement of components of the deposition holder,and the like, are conducted in the disposition chambers 526 p, 526 g,526 r, 526 s. The EL materials are accommodated in advance in thecontainers (typically, crucibles) by material makers. The disposition ispreferably conducted without contact with the atmosphere, and whentransported from material makers, the crucibles are introduced into thedisposition chambers in a state in which they are air-tightly sealed ina second container. The disposition chambers are evacuated, thecrucibles are removed from the second containers In the dispositionchambers, and the crucibles are disposed in the deposition holders. Inthis case, the crucibles and EL materials accommodated in the cruciblescan be prevented from contamination.

In accordance with the present invention, because a white light-emittingelement with a three-layer structure of a layer comprising an organiccompound was realized, the formation of the layer comprising the organiccompound may be conducted with a three-chamber configuration at aminimum. Employing three chambers can shorten the process time and alsocan reduce the cost of production apparatus. Furthermore, the thicknessof each film may be as small as 20 nm-40 nm which is also advantageousfrom the standpoint of material cost.

For example, when a white light-emitting element is formed, a holetransfer layer (HTL) serving as a first light-emitting layer may bedeposited in a film forming chamber 506W1, a second light-emitting layermay be deposited in a film depositing chamber 506W2, an electrodetransfer layer (ETL) may be deposited in the film forming chamber 506W3,and then a cathode may be formed in a film forming chamber 510. A bluefluorescent material having hole transfer capability, such as TPD andα-NPD, may be used as the light-emitting material in the firstlight-emitting layer. An organometallic complex comprising platinum as acentral metal is effective as a light-emitting material in the secondlight-emitting layer. More specifically, if a substance represented bythe following structural formulas (1)-(4) is admixed to a host materialat a high concentration (10 wt. %-40 wt. %, preferably 12.5 wt.-20 wt.%), then both the phosphorescent emission and excimer emission thereofcan be led out. The present invention is, however, not limited to thosematerials and any material may be used, provided that it is aphosphorescent material generating phosphorescent emission and excimeremission at the same time.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

Furthermore, examples of electron transfer materials that can be usedfor the electron transfer layer (ETL) include metal complexes such astris(8-quinolinolato)aluminum (abbreviation: Alq₃),tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq₃), bis(10-hydroxybenzo[h]-quinolinolato)beryllium (abbreviation: BeBq₂),bis(2-methyl-8-quinolinolato)-(4-hydroxy-biphenylyl)-aluminum(abbreviation: BAlq), bis[2-(2-hydroxyphenyl)-benzoxalato]zinc(abbreviation: Zn(BOX)₂), bis[2-(2-hydroxyphenyl)-benzothiazolato]zinc(abbreviation: Zn(BTZ)₂). Examples of suitable compounds other thanmetal complexes include oxadiazole derivatives such as2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation:PBD), and 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene(abbreviation: OXD-7), triazole derivatives such as3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole(abbreviation: TAZ) and3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole(abbreviation: p-EtTAZ), imidazole derivatives such as2,2′,2″-(1,3,5-benzenetriyl)tris[1-phenyl-1H-benzimidazole](abbreviation: TPBI), and phenanthroline derivatives such asbathophenanthroline (abbreviation: BPhen) and bathocuproine(abbreviation: BCP).

In particular, in the second light-emitting layer, a metal complex ofone kind may be admixed at a high concentration (10 wt. %-40 wt. %,preferably 12.5 wt. %-20 wt. %) by co-deposition. Therefore,concentration control is facilitated and the process is suitable formass production.

Further, a simple mask for deposition in the region outside the locationwhere a lead-out electrode is exposed (location where a FPC will bethereafter pasted) may be used as the deposition mask.

In order to obtain a double-side light-emitting panel, the cathode canbe a laminate of a thin metal film and a transparent conductive film.The thin metal film (Ag or MgAg) may be with a thickness of 1 nm-10 nmby a resistance heating method, and a transparent conductive film isformed by sputtering. Therefore, the cathode can be formed within ashort time.

Here an example of fabricating a white light-emitting panel wasdescribed, but panels with monochromatic light emission (green light,red light, blue light, and the like) can be also fabricated.

Described hereinbelow is a procedure in which a substrate that wasprovided in advance with an anode (first electrode) and an insulator(partition wall) for covering the end portions of the anode istransported into the production apparatus shown in FIG. 5 and a lightemitting device is fabricated. When a light-emitting device of an activematrix type is fabricated, a plurality of thin-film transistorsconnected to the anode (TFT for current control) and other thin filmtransistors (TFT for switching and the like) are provided in advance onthe substrate and a drive circuit composed of a thin-film transistor isalso provided. Further, fabrication with the production apparatus shownin FIG. 5 can be also conducted when a light-emitting device of a simplematrix type is fabricated.

The aforementioned substrate (600 mm×720 mm) is set into a substrateplacing chamber 520. The substrate size is 320 mm×400 mm, 370 mm×470 mm,550 mm×650 mm, 600 mm×720 mm, 680 mm×880 mm, 1000 mm×1200 mm, 1100mm×1250 mm. Even a substrate with a surface area as large as 1150×1300can be processed.

The substrate (the substrate provided with an anode and an insulatorcovering the end portions of the anode) set into the substrate placingchamber 520 is transported into a transportation chamber 518 maintainedunder atmospheric pressure. A transportation mechanism (transportationrobot or the like) for transporting and turning over the substrate isprovided in the transportation chamber 518.

Further, respective transportation mechanisms and evacuation means areprovided in the transportation chambers 508, 514, 502. The robotprovided in the transportation chamber 518 can turn the substrate overand can turn it over and transport into a receiving chamber 505. Thereceiving chamber 505 is linked to an evacuation chamber and can beevacuated to vacuum. Upon evacuation, an inactive gas can be introducedto obtain the atmospheric pressure.

A turbomolecular pump of a magnetic levitation type, a cryopump, or adry pump is provided as the aforementioned evacuation chamber. As aresult, the attained degree of vacuum in the transportation chamberslinked to various chambers can be reduced to 10⁻⁵-10⁻⁶ Pa. Further, areverse diffusion of impurities from the pump or evacuation system canbe controlled. An inactive gas such as nitrogen or rare gas is used asthe gas introduced into the apparatus in order to prevent impuritiesfrom penetrating into the apparatus. Those gases that are introducedinto the apparatus are purified to a high degree of purity with a gaspurifier prior to introduction into the apparatus. Therefore, a gaspurifier has to be provided so that the gases are introduced into thedeposition apparatus after purification. In this case, oxygen or waterand other impurities contained in the gases can be removed in advance.Therefore, those impurities can be prevented from being introduced intothe apparatus.

Further, prior to setting into the substrate placing chamber 520,surface dust is preferably removed by washing the surface of the firstelectrode (anode) with a porous sponge (typically made from PVA(polyvinyl alcohol), Nylon, and the like) Impregnated with a surfactant(with weak alkaline properties) in order to reduce point defects. Awashing apparatus comprising a roll brush (manufactured from PVA) whichrotates around an axial line parallel to the substrate surface and is incontact with the substrate surface may be used or a washing apparatuscomprising a disk brush (manufactured from PVA) which rotates around anaxial line perpendicular to the substrate surface and is in contact withthe substrate surface may be used as the cleaning mechanism.

The substrate is then transported from the transportation chamber 518into the receiving chamber 505, and the substrate is then transportedfrom the receiving chamber 505 into the transportation chamber 502,without contact with the atmosphere.

Further, in order to prevent shrinking, vacuum heating is preferablyconducted immediately prior to depositing a film containing an organiccompound. Thus, the substrate is transported from the transportationchamber 502 into a multistage vacuum heating chamber 521 and annealingfor degassing is carried out under vacuum (5×10⁻³ Torr (0.665 Pa) orbelow, preferably, 10⁻⁴-10⁻⁶ Pa) in order to remove thoroughly moistureand other gases contained in the substrate. In the multistage vacuumheating chamber 521, a plurality of substrates are uniformly heated byusing flat-plate heaters (typically, sheath heaters). A plurality ofsuch flat-plate heaters are disposed and heating can be conducted fromboth sides, so that the substrates are sandwiched between the flat-plateheaters. It goes without saying that heating can be also conducted fromone side. In particular, when an organic resin film is used as amaterial for an insulating film or partition wall, because some oforganic resin materials easily adsorb moisture and there is a risk ofdegassing, an effective approach is to conduct heating at a temperatureof 100° C.-250° C., preferably 150° C.-250° C., for example, for 30 minor longer and then conduct natural cooling for 30 min and vacuum heatingto remove the adsorbed moisture prior to forming a layer containing theorganic compound.

Further, UV irradiation may be employed, while conducting heating at atemperature of 200-250° C. in an inactive gas atmosphere, in addition tothe aforementioned vacuum heating. Further, the treatment of irradiatingwith UV rays, while conducting heating at a temperature of 200-250° C.in an inactive gas atmosphere, may be also conducted without conductingvacuum heating.

Further, if necessary, a hole injection layer composed of a polymermaterial may be formed by an ink-jet method, spin coating method, orspray method under an atmospheric pressure or reduced pressure in thefilm forming chamber 512. After coating with the ink-jet method, auniform film thickness may be obtained with a spin coater. Similarly,after coating with the spray method, a uniform film thickness may beobtained with a spin coater. A film may be also formed by the ink-jetmethod in vacuum with vertical parallel arrangement of substrates.

For example, a poly(ethylene dioxythiophene)/poly(styrenesulfonic acid)aqueous solution (PEDOT/PSS), polyaniline/camphorsulfonic acid aqueoussolution (PANI/CSA), PTPDES. Et-PTPDEK, or PPBA used as a hole injectionlayer (anode buffer layer) may be coated and fired over the entiresurface on the first electrode (anode) in the film forming chamber 512.The firing is preferably conducted in the multistage heating chambers523 a, 523 b.

When the hole injection layer (HIL) composed of a polymer material isformed with a coating method using a spin coater or the like, theflatness is increased and coverage of the film formed thereon and theuniformity of film thickness can be improved. In particular, because thefilm thickness of the light-emitting layer is uniform, homogeneous lightemission is obtained. In this case, after the hole injection layer hasbeen formed by the coating method, heating under atmospheric pressure orvacuum heating (100-200°) is preferably conducted immediately prior tofilm formation by a deposition method.

For example, the formation of an EL layer may be carried out by thedeposition method, without contact with air, by washing the surface ofthe first electrode (anode) with a sponge, transporting into thesubstrate placing chamber 520, transporting into the film formingchamber 512 a, coating a poly(ethylenedioxythiophene)/poly(styrenesulfonic acid) aqueous solution (PEDOT/PSS),over the entire surface to a film thickness of 60 nm by a spin coatingmethod, then transporting into multistage heating chambers 523 a, 523 b,pre-firing for 10 min at a temperature of 80° C., main firing for 1 h ata temperature of 200° C., then transporting into a multistage vacuumheating chamber 521, vacuum heating (170° C., heating 30 min, cooling 30min) immediately prior to deposition, and then transporting into filmforming chambers 506W1, 506W2, and 506W3. In particular, when an ITOfilm is used as an anode material and peaks and valleys of fineparticles are present on the surface, the effect thereof can be reducedby forming the PEDOT/PSS film to a thickness of 30 nm or more. Further,it is preferred that ultraviolet irradiation be carried out in the UVtreatment chamber 531 in order to improve wettability of PEDOT/PSS.

Further, when a PEDOT/PSS film is formed by a spin coating method, thefilm is formed over the entire surface. Therefore, it is preferred thatthe end surfaces or peripheral edges of the substrate, terminalportions, and zones of contact with the cathode and lower wiring beselectively removed. The selective removal is preferably conducted by O₂ashing by using a mask in a pretreatment chamber 503. The pretreatmentchamber 503 comprises plasma generation means and dry etching isconducted therein by exciting one or a plurality of gases selected fromAr, H, F, and O and generating plasma. Using a mask makes it possible toremove selectively only the unnecessary portions.

Further, the deposition masks are stocked in mask stock chambers 524 a,524 b and appropriately transported into the film forming chamber whendeposition is conducted. If a large substrate is used, then the surfacearea of the mask increases. As a result, a frame for fixing the maskbecomes larger and a large number of masks are difficult to stock. Forthis reason, here, two mask stock chambers 524 a, 524 b were prepared.Cleaning of deposition masks may be conducted in the mask stock chambers524 a, 524 b. Further, during deposition, the mask stock chambers areempty. Therefore, substrates can be stocked therein after film formationor treatment.

The substrates are then transported from the transportation chamber 502into the receiving chamber 507 and then the substrates are transportedfrom the receiving chamber 507 into the transportation chamber 508,without contact with air.

The substrates are then appropriately transported into film formingchambers 506W1, 506W2, 506W3 linked to the transportation chamber 508and organic compound layers composed of low-molecular materials andserving as the hole transfer layer, light-emitting layer, and electrontransfer layer are appropriately formed. Appropriately selecting the ELmaterial makes it possible to form a light-emitting elementdemonstrating monochromatic (more specifically, white) light emission asthe entire light emitting element. Further substrate transportationbetween the transportation chambers is conducted via the receivingchambers 540, 541, 511, without contact with air.

Then, the substrates are transported into the film forming chamber 510by the transportation mechanism disposed in the transportation chamber514 and a cathode is formed. The cathode is preferably transparent orsemitransparent. It is preferred that the cathode be formed from a thin(1 nm-10 nm) metal film (alloys such as MgAg, MgIn, CaF₂, LiF, and CaN,or films formed by co-deposition of an element of Group 1 or Group 2 ofthe periodic table of the elements and aluminum, or laminated films ofthose films) formed by a deposition method using resistance heating or alaminate of such thin metal film (1 nm-10 nm) and a transparentconductive film. After the substrates have been transported from thetransportation chamber 508 into the transportation chamber 514 via thereceiving chamber 511, they are transported into the film formingchamber 509 and a transparent conductive film is formed by using asputtering method.

A light-emitting element of a laminated structure having a layercomprising an organic compound is formed by the above-described process.

It is also possible to conduct sealing by transporting into a filmforming chamber 513 linked to the transportation chamber 514 and forminga protective film composed of a silicon nitride film or a siliconnitride oxide film. Here, a target composed of silicon, a targetcomposed of silicon oxide, or a target composed of silicon nitride oxideis provided inside the film forming chamber 513.

Further, a protective film may be formed by moving a rod-like targetwith respect to the fixed substrate. Further, a protective film may beformed by moving the substrate with respect to a fixed rod-like target.

For example, a silicon nitride film can be formed an the cathode byusing a disk-like target composed of silicon and employing a nitrogenatmosphere or an atmosphere comprising nitrogen and argon as theatmosphere of the film forming chamber. Further, a thin film comprisingcarbon as the main component (DLC film, CN film, amorphous carbon film)may be formed as the protective film, and a film forming chamber using aCVD method may be provided separately. A diamond-like carbon film (alsocalled a DLC film) can be formed by a plasma CVD method (typically, a RFplasma CVD method, microwave CVD method, electron cyclotron resonance(ECR) CVD method, thermal filament CVD method, and the like), combustionflame method, sputtering method, ion beam deposition method, laserdeposition method and the like. Hydrogen gas and a hydrocarbon gas (forexample, CH₄, C₂H₂, C₆H₆, and the like) is used as the reaction gasemployed for film formation and the film is formed by ionization with aglow discharge and acceleration bombardment with the ions of the cathodewith a negative self-bias applied thereto. Further, a CN film may beformed by using C₂H₄ gas and N₂ gas as the reaction gas. The DLC filmand CN film are insulting films transparent or semitransparent tovisible light. Transparency to visible light indicates a transmittanceof visible light of 80-100%, and semitransparency to visible lightindicates a transmittance of visible light of 50-80%.

Further, a protective film composed of a laminate of a first inorganicinsulating film, a stress relaxation film, and a second inorganicinsulating film may be formed instead of the above-described protectivefilm on the cathode. For example, it may be formed by forming a cathode,then transporting into the film forming chamber 513, forming a firstinorganic insulating film to 5 nm-50 nm, transporting to the filmforming chamber 506W1, 506W2, or 506W3, forming a stress relaxation filmhaving moisture absorptivity and transparency by a deposition method(inorganic layer or a layer comprising an organic compound) to 10 nm-100nm, then again transporting to the film forming chamber 513 and forminga second inorganic insulating film to 5 nm-50 nm.

The substrate having the light-emitting elements formed thereon is thentransported to a sealing chamber 519.

A sealing substrate is set from the outside into the loading chamber 517and prepared. The sealing substrate is transported from the loadingchamber 517 into the transportation chamber 527 and into an optical filmattaching chamber 529 for attaching an optical filter (color filter,polarizing film, and the like) and, if necessary, a drying agent.Further, a sealing substrate which has an optical film (color filter,polarizing plate) attached thereto in advance may be also set into theloading chamber 517.

Further, annealing is preferably carried out in advance in a multistageheating chamber 516 to remove impurities such as moisture present in thesealing substrate. Further, when a sealing material for pasting to thesubstrate provided with the light-emitting element is formed on thesealing substrate, the sealing material is formed in a dispenser chamber515, the sealing substrate with the sealing material formed thereon istransported into the transportation chamber 514 via the receivingchamber 542 and then to the sealing substrate stock chamber 530. Here,an example was presented in which the sealing material was formed on thesealing substrate, but this example is not limiting and the sealingmaterial may be formed on the substrate where the light-emitting elementwas formed. Further, deposition masks used during deposition may be alsostocked in the sealing substrate stock chamber 530.

Further, because the present example relates to a double-side emissionstructure, the sealing substrate may be transported to the optical filmattachment chamber 529 and an optical film may be attached to the innerside of the sealing substrate. Alternatively, the substrate providedwith the light-emitting element may be bonded to the sealing substrateand then transported into the optical film attachment chamber 529, wherean optical film (color filter or polarizing plate) may be attached tothe outer side of the sealing substrate.

Then, the substrate and sealing substrate are bonded in the sealingchamber 519 and the sealing material is cured by irradiating the pair ofbonded substrates with UV rays by using the UV irradiation mechanismprovided in the sealing chamber 519. It is preferred that irradiationwith U rays be conducted from the side of the sealing substrate whereTFTs, which shield the light, are not provided. Further, a UV-curableand heat-curable resin was used as a sealing material, but no limitationis placed thereon, provided that it is an adhesive material. Forexample, a resin curable only with UV rays may be used.

Further, the air-tight space may be filled with a resin rather than withan inactive gas. When UV irradiation is conducted from the side of thesealing substrate in case of bottom-side emission type, the light doesnot pass through the cathode. Therefore, no limitation is placed on theresin material for filling and a UV-curable resin or non-transparentresin may be used. However, when irradiation with UV rays is conductedfrom the side of the sealing substrate in case of double-side emission,the UV rays pass through the cathode and the EL layer is damaged.Accordingly, it is preferred that UV-curable resin be not used.Therefore, in case of double-side emission type, it is preferred that athermosetting transparent resin be used as the resin for filling.

Then, the pair of bonded substrates are transported from the sealingchamber 519 to the transportation chamber 514 and then via the receivingchamber 542 from the transportation chamber 527 to a removal chamber 525for removal.

Upon removal from the removal chamber 525, heating is conducted and thesealing material is cured. In case of upper surface emission and fillingwith a thermosetting resin, curing can be conducted simultaneously withheat treatment conducted to cure the sealing material.

As described hereinabove, with the production apparatus shown in FIG. 5,the light-emitting elements are not exposed to air till they are sealedin an air-tight space. Therefore, highly reliable light-emitting devicescan be fabricated.

A control unit (not shown in the figures) is provided for realizing fullautomation by controlling a path of moving the substrates throughindividual treatment chambers.

Example 2

FIG. 6 is an example of the top view of a deposition apparatus.

Referring to FIG. 6, a film forming chamber 101 comprises a substrateholding means (not shown in the figures), a first deposition sourceholder 104 a and a second deposition source holder 104 b havingdeposition shutters (not shown in the figures) disposed therein, means(not shown in the figure) for moving those deposition source holders,and means (evacuation means) for creating the atmosphere under reducedpressure. The film forming chamber 101 is evacuated to a vacuum degreeof 5×10⁻³ Torr (0.665 Pa) or less, preferably to 10⁻⁴-10⁻⁶ Pa with themeans for creating the atmosphere under reduced pressure.

Further, a gas introduction system (not shown in the figures) forintroducing a material gas at several sccm during deposition andinactive gas (Ar, N₂, and the like) introduction system (not shown inthe figures) for creating normal pressure inside the film formingchamber are linked to the film forming chamber. Further, a cleaning gas(one or several gases selected from H₂, F₂, NF₃, or O₂) introductionsystem may be also provided. It is preferred that the material gas doesnot flow to the gas release opening at the shortest distance from thegas introduction opening.

A high-density film may be obtained by introducing the material gasintentionally during film formation and including the components of thematerial gas into the organic compound layer, and permeation anddiffusion of impurities such as oxygen or moisture that causedeterioration into the film may be blocked. Specific examples of thematerial gas include one or a plurality of gases selected from silanegases (monosilane, disilane, trisilane, and the like), SiF₄, GeH₄, GeF₄,SnH₄, or hydrocarbon gases (CH₄, C₂H₂, C₂H₄, C₆H₆, and the like).Further, a gas mixture obtained by diluting those gases with hydrogen,argon, or the like, is also included. Those gases that are introducedinto the apparatus are purified to a high degree of purity with a gaspurifier prior to introduction into the apparatus. Therefore, a gaspurifier has to be provided so that the gases are introduced into thedeposition apparatus after purification. In this case, residual gases(oxygen, water and other impurities) contained in the gases can beremoved in advance. Therefore, those impurities can be prevented frombeing introduced into the apparatus.

For example, when defective portions such as pinholes and short circuitsoccur after Si was included in the film by introducing monosilane gasduring deposition and the light-emitting elements were produced, aself-healing effect can be obtained in which the Si participates in areaction due to heat generation in those defective portions and forms aninsulator with insulating properties such as SiOx and SiCx, leakage inthe pinholes and short circuit portions is reduced, and the developmentof point defects (dark spots and the like) is prevented.

Further, when the aforementioned material gas is introduced, aturbomolecular pump or dry pump is preferably provided in addition to acryopump.

Further, in the film forming chamber 101, the deposition source holder104 can move many times along the movement path shown by a chain line inFIG. 6. The movement path shown in FIG. 6 is merely an example and isnot limiting. In order to obtain a uniform film thickness, it ispreferred that the deposition source holder be moved by shifting themovement path as shown in FIG. 6 and deposition be conducted. Further,reciprocal movement along the same movement path is also possible. Thefilm thickness uniformity may be improved and time required to deposit afilm may be shortened by appropriately changing the movement rate of thedeposition holder for each segment of the movement path. For example,the deposition source holder may be moved in the X direction or Ydirection at a rate of 30 cm/min to 300 cm/min.

Further, when a white light-emitting element is fabricated, depositionmay be conducted locally, as shown in FIG. 9. The deposition isconducted locally so that at least a region that will be a displayregion is contained in the region that will be a panel. Conducting thedeposition locally prevents the deposition on the regions where thedeposition is not required. A shutter (not shown in the figure) is usedfor local deposition and the deposition is conducted without a mask, byappropriately opening and closing the shutter. FIG. 9 shows an examplein which gang printing is carried out. Here, the reference symbol 900stands for a large substrate, 901—a film forming chamber, 904—a movabledeposition holder, and 906—a crucible.

Further, a container (crucible 106) with the deposition materialintroduced therein is disposed in the deposition source holders 104 a,104 b. In the example shown herein, two crucibles are disposed in onedeposition source holder 104 a, 104 b. Another specific feature is thata film thickness meter (not shown in the figure) is provided in thedisposition chamber 103. Here, monitoring with the film thickness meteris not conducted while the deposition source is moved and the frequencyof replacing the film thickness meter is reduced.

When there are several containers (crucibles and deposition boatsaccommodating organic compounds) provided in one deposition sourceholder, the mounting angles of the crucibles are preferably selected sothat the directions (evaporation centers) of evaporation that allow theorganic compounds to be mixed together intersect in the position of thedeposition object.

Further, the deposition source holder is constantly in a stand-by modein a disposition chamber for crucibles and heating and temperatureholding are carried out till the deposition rate is stabilized. A filmthickness monitor (not shown in the figure) is disposed in thedisposition chamber for crucibles. Once the deposition rate hasstabilized, the substrate is transported into the film forming chamber102 and alignment with a mask (not shown in the figure) is conducted.Then, the shutter is opened and the deposition holder is moved. Here,the alignment of the deposition mask or substrate is preferablyconfirmed by using a CCD camera (not shown in the figure). Positioncontrol may be carried out by providing respective alignment markers onthe substrate and deposition mask. Once the deposition has beencompleted, the deposition holder is moved to the disposition chamber forcrucibles and the shutter is closed. Once the shutter has been closed,the substrate is transported into the transportation chamber 102.

Further, referring to FIG. 6, a plurality of deposition holders 104 a,104 b are in a stand-by mode in the disposition chamber 103, and oncethe material located in one deposition holder has been consumed, thisdeposition holder is replaced with another deposition holder and filmformation can be carried out in a continuous mode by successively movingthe deposition holders. While one deposition holder is moved in the filmforming chamber, the emptied deposition holder can be refilled with theEL material. Using a plurality of deposition holders 104 makes itpossible to form a film efficiently.

Further, only two crucibles can be set into the deposition holders 104a, 104 b, but the deposition may be conducted by setting four cruciblesor by setting two or only one crucible.

In accordance with the present invention, the time required for filmdeposition can be reduced. In prior art when the EL material wasreplenished, it was necessary to open the film forming chamber toatmosphere, refill the crucibles and then evacuate the chamber.Therefore, a long time was required for refilling, causing decrease inthroughput.

Further, if it were possible to reduce also the adhesion to the innerwalls of the film forming chamber, the maintenance frequency such ascleaning of the inner walls of the film forming chamber could bedecreased.

Further, disposing the crucibles 106 in the deposition holders 104 a,104 b is also conducted in the disposition chamber 103 b. Thetransportation pattern is shown in FIG. 7(A) and FIG. 7(B). Componentscorresponding to those shown in FIG. 6 are assigned with identicalreference symbols. The crucible 106 air-tightly sealed under vacuum in acontainer composed of an upper part 721 a and a lower part 721 b isinserted from a door 112 of the disposition chamber 103. First, theinserted container is placed on a rotary stand 109 for containerdisposition and a latch 702 is released. Because the inside (FIG. 7(A))is under vacuum, the removal under atmospheric pressure is impossibleeven if the latch 702 is released. The disposition chamber 103 a is thenevacuated, and a state is assumed in which the lid (upper part 721 a) ofthe container can be removed.

The form of the transported container will be described specificallywith reference to FIG. 7(A). A second container divided into an upperpart (721 a) used for transportation and a lower part (721 b) comprisesfixing means 706 for fixing a first container (crucible) provided in theupper part of the second container, a spring 705 for applying pressureto the fixing means, a gas introducing opening 708 serving as a gas pathfor maintaining a reduced pressure in the second container provided inthe lower part of the second container, an O ring for fixing the uppercontainer 721 a and the lower container 721 b, and a latch 702. A firstcontainer 106 having a purified deposition material inserted therein isdisposed inside the second container. Further, the second container maybe formed from a material comprising a stainless steel, and the firstcontainer 106 may be formed from a material comprising titanium.

The purified deposition material is inserted into the first container106 by the material maker. Then, the second upper part 721 a and lowerpart 721 b are mated via the O ring, the upper container 721 a and lowercontainer 721 b are fixed with the latch 702, and the first container106 is air-tightly sealed inside the second container. Then, thepressure inside the second container is reduced via the gas introducingopening 708, the atmosphere is replaced with a nitrogen atmosphere, andthe spring 705 is adjusted to fix the first container 106 with thefixing means 706. A drying agent may be disposed inside the secondcontainer. If the inside of the second container is thus maintainedunder vacuum or reduced pressure and nitrogen atmosphere, the adhesionof even slight amounts of oxygen or water to the deposition material canbe prevented.

Then, the lid of the container is lifted and moved to a stand 107 forlid disposition by a robot 108 for lid transportation. Thetransportation mechanism in accordance with the present invention is notlimited to the configuration in which the first container is transportedwhile being held from above the first container 106, as described withreference to FIG. 7(B), and a configuration may be used in which it istransported while being held on the side surfaces of the firstcontainer.

Further, after the rotary stand 109 for container disposition has beenrotated, only the crucible is lifted by a robot 110 for crucibletransportation, while the lower part of the container is being left onthe stand (FIG. 7(B)). Finally, the crucible is set into the depositionholders 104 a, 104 b that were waiting in the disposition chamber 103.

The disposition chamber 103 may be provided with a cleaning gas (one orseveral gases selected from H₂, F₂, NF₃, or O₂) and the components suchas the deposition holders and shutter may be cleaned by using thecleaning gas. Further, it is also possible to clean the components suchas the inner walls of the disposition chamber, deposition holder, andshutter by providing plasma generating means and generating plasma or byintroducing gas ionized by plasma into the disposition chamber and torelease gas with vacuum gas release means. Plasma for cleaning may begenerated by exciting one or a plurality of gases selected from Ar, N₂,H₂, F₂, NF₃, or O₂.

The degree of cleaning of the film forming chamber can be thusmaintained by moving the deposition holders 104 a, 104 as far as thedisposition chamber 103 and conducting cleaning in the dispositionchamber.

Further, this example can be freely combined with Example 1. Thedeposition apparatus shown in FIG. 6 may be disposed in any of the filmforming chambers 506W1, 506W2, 506W3 shown in FIG. 5 and the dispositionchamber shown in FIG. 7 may be disposed in the disposition chambers 526a-526 n shown in FIG. 5.

Example 3

An example of the film forming chamber allowing the cleaning of theinside of the film forming chamber and the deposition mask to beconducted without opening the chamber to the atmosphere is shownhereinbelow. FIG. 8 is an example of the cross-sectional view of thefilm forming apparatus of the present example.

In the example shown in FIG. 8, plasma 1301 is generated between adeposition mask 1302 a and an electrode 1302 b connected via ahigh-frequency power source 1300 a and a capacitor 1300 b.

Referring to FIG. 8, the deposition mask 1302 fixed in a holder isinstalled close to a place (a place shown by a dot line in the figure)where the substrate is provided, and a deposition source holder 1322that can conduct heating to respective different temperatures isprovided therebelow. The deposition source holder 1322 can be moved withmovement mechanism 1328 In the X direction, Y direction, Z direction, orθ direction which is a rotation direction.

If the organic compound located inside is heated to a sublimationtemperature with heating means (typically, a resistance heating method)disposed in the deposition holder, the organic compound is gasified anddeposited on the substrate surface. During deposition, the substrateshutter 1320 is moved to a position in which it does not impede thedeposition. Further, a shutter 1321 that moves together with thedeposition holder is also provided therein and when deposition is to beconducted, it is moved into a position in which it does not impede thedeposition.

Further, a gas introduction system is provided such that duringdeposition, a gas composed of particles smaller than the particles ofthe organic compound material, that is, a gas composed of a materialwith a small atomic radius can be passed in a very small quantity and amaterial with a small atomic radius can be introduced into the organiccompound film. Specific examples of gases that may be used as the gas ofmaterial with a small atomic radius include one or a plurality of gasesselected from silane gases (monosilane, disilane, trisilane, and thelike), SiF₄, GeH₄, GeF₄, SnH₄, or hydrocarbon gases (CH₄, C₂H₂, C₂H₄,C₆H₆, and the like). Further, a gas mixture obtained by diluting thosegases with hydrogen, argon, or the like, is also included. Those gasesthat are introduced into the apparatus are purified to a high degree ofpurity with a gas purifier prior to the introduction into the apparatus.Therefore, a gas purifier has to be provided so that the gases areintroduced into the deposition apparatus after purification. In thiscase, residual gases (oxygen, water and other impurities) contained inthe gases can be removed in advance. Therefore, those impurities can beprevented from being introduced into the apparatus.

For example, when defective portions such as pinholes and short circuitsoccur after Si was included in the film by introducing monosilane gasduring deposition and the light-emitting elements were produced, aself-healing effect can be obtained in which the Si participates in areaction due to heat generation in those defective portions and forms aninsulator with insulating properties such as SiOx and SiCx, leakage inthe pinholes and short circuit portions is reduced and development ofpoint defects (dark spots and the like) is prevented.

The components of the introduced material gas may be deposited with goodefficiency on the substrate by heating the substrate with heating meanssuch as a heater 1304 for substrate heating.

Further, radicals may be produced with plasma generation means. Forexample, in case of monosilane, a silicon oxide precursors such as SiHx,SiHxOy, and SiOy are formed with plasma generation means and they aredeposited together with the organic compound material from theevaporation source on the substrate. Monosilane easily reacts withoxygen or moisture and the concentration of oxygen or quantity ofmoisture in the film forming chamber can be reduced.

A turbomolecular pump 1326 of a magnetic levitation type and a cryopump1327 are provided as a vacuum gas release chamber to enable theintroduction of a variety of gases. As a result, the attained degree ofvacuum in the film forming chamber can be reduced to 10⁻⁵-10⁻⁶ Pa. Aftervacuum gas release with the cryopump 1327, the cryopump 1327 is stoppedand deposition is conducted, while conducting vacuum gas release withthe turbomolecular pump 1326 and passing the material gas at severalsccm. Further, an ion plating method may be used and the deposition maybe carried out, while ionizing the material gas inside the film formingchamber and causing it to adhere to the evaporated organic material.

Upon completion of deposition, the substrate is removed and cleaning iscarried out for removing the deposition material that adhered to theinner walls of the film forming apparatus and jigs provided inside thefilm forming apparatus, without opening to the atmosphere.

Further, it is preferred that the deposition holder 1322 be moved to thedisposition chamber (not shown in the figures) during cleaning.

In the course of the cleaning a wire electrode 1302 b is moved to theposition facing the deposition mask 1302 a. Further, a gas is introducedinto the film forming chamber 1303. One gas or a plurality of gasesselected from Ar, H₂, F₂, NF₃, or O₂ may be used as the gas introducedinto the film forming chamber 1303. Further, plasma 1301 is generated byapplying high-frequency electric field to the deposition mask 1302 afrom a high-frequency power source 1300a and exciting the gas (Ar. H. F,NF₃, or O) Plasma 1301 is thus generated inside the film forming chamber1303, and the deposited matter that adhered to the inner walls of thefilm forming chamber, a deposition-preventing shield 1305, or thedeposition mask 1302 is gasified and released to the outside of the filmforming chamber. With the film forming apparatus shown in FIG. 4,cleaning can be conducted without exposing the inside of the filmforming chamber or deposition mask to the atmosphere during maintenance.

Here, an example was shown in which plasma was induced between thedeposition mask 1302 a and the electrode 1302 b disposed between themask and the deposition source holder 1306, but this example is notlimiting as long as plasma generation means is employed. Further, ahigh-frequency powder source may be connected to the electrode 1302 band the wire electrode 1302 b may be in the form of a plate-like ormesh-like electrode and it may be an electrode capable of introducing agas as a shower head. An ECR, ICP, helicon, magnetron, two-period wave,triode, LEP, or the like, can be appropriately used as a plasmageneration method.

Further, the above-described plasma cleaning may be conducted for eachcycle of film forming process or can be conducted after several cyclesof the film forming process have been completed.

Further, this example can be freely combined with any of Embodiments 1to 4, Example 1, and Example 2.

Example 4

In the present working example, an example of fabricating alight-emitting device (double-side emission structure) comprising alight-emitting element employing an organic compound layer as alight-emitting layer on a substrate having an insulated surface is shownin FIG. 12.

Further, FIG. 12(A) is a top view of the light-emitting device, FIG.12(B) is a cross-sectional view obtained by cutting FIG. 12(A) alongA-A′. The reference numeral 1101 stands for a source signal line drivecircuit (shown by a dot line), 1102—a pixel unit, 1103—a gate signalline drive circuit. Further, the reference numeral 1104 stands for atransparent sealing substrate and 1105—a first sealing material. Thespace surrounded by the first sealing material 1105 is filled with atransparent second sealing material 1107. The first sealing material1105 comprises a gaps material for maintaining the substrate clearance.

Further, the reference numeral 1108 stands for a wiring for transmittingsignals inputted into the source signal line drive circuit 1101 and gatesignal line drive circuit 1103. It receives a video signal or clocksignal from a FPC (flexible printed circuit) 1109 serving as an externalinput terminal. Here, only the FPC is shown, but a printed wiring board(PWB) may be mounted on the FPC.

The cross-sectional configuration will be explained below by using FIG.12(B). A drive circuit and an Image portion are formed on a transparentsubstrate 1110. Here, the source signal line drive circuit 1101 as thedrive circuit and the image portion 1102 are shown.

A CMOS circuit combining a n-channel TFT 1123 and a p-channel TFT 1124is formed as the source signal line drive circuit 1101. The TFT formingthe drive circuit may be formed from a well-known CMOS circuit, PMOScircuit, or NMOS circuit. Furthermore, in the present working example, adriver-unified configuration is shown in which the drive circuit isformed on the substrate, but such a configuration is not alwaysnecessary and the drive circuit can be formed on the outside, ratherthan on the substrate. Further, the structure of a TFT in which apolysilicon film or amorphous silicon film serves as an active layer isnot particularly limiting, and a top-gate TFT or a bottom-gate TFT maybe used.

Further, the pixel portion 1102 is composed of a plurality of pixelscomprising a TFT 1111 for switching, a TFT 1112 for current control, anda first electrode (anode) 113 electrically connected to the drainthereof. An n-channel TFT or a p-channel TFT may be used as the TFT 1112for current control, but when connection is made to the anode, thep-channel TFT is preferably used. Further, it is preferred that anappropriate holding capacitance (not shown in the figure) be provided.Here, only the cross-sectional structure of one pixel of an extremelylarge number of pixels is shown and an example is shown in which twoTFTs were used for this one pixel, but three or more TFT may be usedappropriately.

In this configuration the first electrode 1113 is directly connected tothe drain of TFT. Therefore, it is preferred that the lower layer of thefirst electrode 1113 be a material layer providing for ohmic contactwith the drain composed of silicon and that the uppermost layer which isin contact with the layer containing an organic compound be a materiallayer with a large work function. For example, a transparent conductivefilm (ITO (indium oxide tin alloy), indium oxide zinc oxide alloy(In₂O₃—ZnO), zinc oxide (ZnO), and the like) is used.

Further, an insulator (called a bank, a partition wall, a separatingwall, an embankment, and the like) 1114 is formed at both ends of thefirst electrode (anode) 1113. The insulator 1114 may be formed from anorganic resin film or an insulating film containing silicon. Here, aninsulator of the shape shown in FIG. 12 is formed as the insulator 1114by using a positive-type photosensitive acrylic resin film.

A curved surface having a curvature is formed at the upper end portionor lower end portion of the insulator 1114 with the object of improvingcoverage. For example, when a positive-type photosensitive acryl is usedas the material of the insulator 1114, it is preferred that the curvedsurface having a curvature radius (0.2 μm-3 μm) be provided only at theupper end portion of the insulator 1114. Furthermore, eithernegative-type photosensitive compositions that are made insoluble in anenchant under light or positive-type compositions that are made solublein an etchant under light can be used as the insulator 1114.

Further, the insulator 1114 may be covered with a protective filmcomposed of an aluminum nitride film, an aluminum nitride oxide film, athin film containing carbon as the main component, or a silicon nitridefilm.

Further, a layer 1115 comprising an organic compound is selectivelyformed by a deposition method on the first electrode (anode) 1113. Inthe present working example, the layer 1115 comprising an organiccompound is formed in the production apparatus described in Embodiment 2and a uniform film thickness is obtained. Furthermore, a secondelectrode (cathode) 1116 is formed on the layer 1115 comprising anorganic compound. A material with a low work function (Al, Ag, Li, Ca,alloys thereof, MgAg, MgIn, AlLi, CaF₂, or CaN) may be used for thecathode. Here, in order to pass the emitted light, a laminated layer ofa thin metal film (MgAg: film thickness 10 nm) with a decreased filmthickness and a transparent electrically conductive film (ITO (indiumoxide tin oxide alloy) with a film thickness of 110 nm, an indium oxidezinc oxide alloy (In₂O₃—ZnO), zinc oxide (ZnO), and the like) is used asthe second electrode (cathode) 1116. A light-emitting element 1118composed of the first electrode (anode) 1113, the layer 1115 comprisingan organic compound, and a second electrode (cathode) 1116 is thusformed. In the present working example, white emitted light is obtainedby use of a layer composed of organic compounds 1115 formed bysuccessively laminating CuPc (film thickness 20 nm), α-NPD (filmthickness 30 nm), CBP (film thickness 30 nm) comprising anorganometallic complex comprising platinum as a central metal (Pt(ppy)acac), BCP (film thickness 20 nm),and BCP:Li (film thickness 40nm). This working example is an example in which the light-emittingelement 1118 emits white light. Therefore, a color filter (here, for thesake of simplicity, the overcoat is not shown in the figure) composed ofa coloration layer 1131 and a light-shielding layer (BM) 1132 isprovided.

Further, in such double-side light-emission display device, opticalfilms 1140, 1141 are provided in order to prevent the background frompenetration and to prevent the external light reflection. A polarizingfilm (a polarizing plate of a high transmittance type, a thin lightpolarizing plate, a white light polarizing plate, a polarizing platecomprising high-performance dyes, an AR polarizing plate, and the like),a phase-difference film (a broadband 1/4ο plate, atemperature-compensated phase-difference film, a twistedphase-difference film, a phase-difference film with a wide viewingangle, a biaxially oriented phase-difference film, and the like), and aluminosity-increasing film may be used in an appropriate combination asthe optical films 1140, 1141. For example, if polarizing films are usedas the optical films 1140, 1141 and arranged so that the lightpolarization directions are orthogonal to each other, it is possible toobtain an effect of preventing the penetration of background and aneffect of preventing the reflection. In this case, zones outside theportions where light is emitted and display is conducted, become blackand the background can be prevented from penetrating and being seen evenwhen the display is viewed from any side. Further, because the emittedlight from the light-emitting panel passes only through one polarizingplate, it is displayed as is.

The same effects as described hereinabove can be obtained in case thateven if the two polarizing films are not orthogonal, the lightpolarization directions are within an angle of ±45°, preferably, within±20° with respect to each other.

With the optical films 1140, 1141, it is possible to prevent thebackground from penetrating, becoming visible and making it difficult torecognize the display when a person views the display from one surface.

Further, one more optical film may be added. For example, one polarizingfilm absorbs S waves (or P waves), but a luminosity increasing film forreflecting S waves (or P waves) onto the light-emitting elements andreproducing them may be provided between the polarizing plate andlight-emitting panel. As a result, the number of P waves (or S waves)that pass through the polarizing plate increases and the increase inintegral quantity of light can be obtained. In the double-sidelight-emitting panels, the structures of layers that pass the light fromthe light-emitting elements are different. Therefore, the light emissionpatterns (luminosity, chromaticity balance, and the like) are differentand the optical films are suitable for adjusting the light emissionbalance on both sides. Further, in the double side light-emittingpanels, the external light reflection intensities are also different.Therefore, it is preferred that the luminosity increasing film beprovided between the polarizing plate and light-emitting panel on thesurface with a larger reflection.

Further, a transparent protective laminated layer 1117 is formed forsealing the light-emitting element 1118. The transparent protectivelaminated layer 1117 is composed of a laminated layer of a firstinorganic insulating film, a stress relaxation film, and a secondinorganic insulating film. A silicon nitride film, silicon oxide film,silicon oxide nitride film (SiNO film (composition ratio N<O). a SiONfilm (composition ratio N<O)), or a thin film containing carbon as themain component (for example, a DLC film, a CN film) obtained by asputtering method or a CVD method can be used as the first inorganicinsulating film and second inorganic insulating film. Those inorganicinsulating films have a strong blocking effect with respect to moisture,but if the film thickness increases, the film stresses increase and thefilm can be easily peeled or detached. However, stresses can be relaxedand moisture can be absorbed by sandwiching a stress relaxation filmbetween the first inorganic insulating film and second inorganicinsulating film. Further, even when fine holes (pinholes and the like)are formed for whatever reason in the first inorganic insulating filmduring deposition, they are filled with the stress relaxation film.Further, providing the second inorganic insulating film thereuponproduces a very strong blocking effect with respect to moisture oroxygen. Further a hygroscopic material with stresses less than those inthe inorganic insulating films is preferred as the stress relaxationfilm. Moreover, a transparent material is preferred. Further, materialfilms comprising organic compounds such as α-NPD(4,4′-bis-[N-(naphthyl)-N-phenyl-amino]biphenyl), BCP (bathocuproine),MTDATA (4,4′,4″-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine),Alq₃ (tris-8-quinolinolatoaluminum complex) may be used as the stressrelaxation film. Those material films have hygroscopicity and are almosttransparent if the film thickness is small. Furthermore, because MgO,SrO₂, and SrO have hygroscopicity and light transparency and thin filmsthereof can be obtained by a deposition method, they can be used for thestress relaxation film. In the present example, a film formed in anatmosphere comprising nitrogen and argon by using a silicon target, thatis, a silicon nitride film with a strong blocking effect with respect tomoisture and impurities such as alkali metals is used as a firstinorganic insulating film or second inorganic insulating film, and athin film of Alq₃ produced by a deposition method is used as the stressrelaxation film. Further, in order to pass the emitted light to thetransparent protective laminated layer, the total film thickness of thetransparent protective laminated layer is preferably as small aspossible.

Further, the sealing substrate 1104 is pasted with a first sealingmaterial 1105 and a second sealing material 1107 under an inactive gasatmosphere in order to seal the light-emitting element 1118. An epoxyresin is preferably used as the first sealing material 1105. Further, nospecific limitation is placed on the second sealing material 1107,provided it is a material transparent to light. Typically, it ispreferred that a UV-curable or thermosetting epoxy resin be used. Here,a UV epoxy resin (manufactured by Electrolight Co., 1500Clear) with highheat resistance is used. This resin has a refractive index of 1.50, aviscosity of 500 cps, a Shore D hardness of 90, a tensile strength of3000 psi, a Tg point of 150° C., a volume resistance of 1×10¹⁵ Ω·cm, anda voltage resistance of 450 V/mil. Further, filling the space between apair of substrates with the second sealing material 1107 makes itpossible to increase the transmittance of the entire body with respectto that obtained when the space between the two substrates is empty(inactive gas). Further, it is preferred that the moisture or oxygenpermeability of the first sealing material 1105 and second sealingmaterial 1107 be as low as possible.

Further, in the present working example, a plastic substrate composed ofFRP (Fiberglass-Reinforced Plastics), PVF (polyvinyl fluoride), Mylar,polyesters, acryls, and the like, can be used besides a substrate orquartz glass substrate as the material constituting the sealingsubstrate 1104. Further, after the sealed substrate 1104 has beenadhesively bonded by using the first sealing material 1105 and secondsealing material 1107, sealing can be conducted with a third sealingmaterial so as to cover the side surfaces (exposed surfaces).

Sealing the light-emitting element with the first sealing material 1105and second sealing material 1107 in the above-described manner makes itpossible to completely shield the light-emitting element from theoutside and to prevent the penetration of substances, such as moistureor oxygen, that enhance the deterioration of the organic compound layer.Therefore, a light-emitting device with high reliability is obtained.

Further, when a light-emitting device of an upper-surface emission typeis fabricated, the cathode is preferably a reflective metal film(chromium, titanium nitride, and the like). Furthermore, when alight-emitting device of a lower-surface emission type is fabricated, ametal film (film thickness 50 nm-200 nm) composed of Al, Ag, Li, Ca,alloys thereof, MgAg, MgIn, and AlLi is preferably used for the cathode.

This example can be freely combined with Embodiments 1 to 4 and Examples1 to 3.

Example 5

In this working example, an electronic device comprising two or moredisplay devices will be explained with reference to FIG. 12. Anelectronic device equipped with an EL module can be created byimplementing the present invention. Examples of electronic devicesinclude video cameras, digital cameras, goggle-type displays(head-mounted displays), navigation systems, acoustic reproductiondevices (car audio, audio component stereo systems, and the like),notebook personal computers, game devices, portable informationterminals (mobile computers, cellular phones, portable game machines,electronic books, and the like), and image reproducing devicescomprising recording medium (more specifically, devices equipped withdisplays capable of reproducing the recorded medium, such as DigitalVersatile Disk. (DVD) and displaying the image).

FIG. 12(A) is a perspective view of a notebook personal computer, FIG.12(B) is a perspective view illustrating the folded state. The note-bookpersonal computer comprises a body 2201, a case 2202, display portions2203 a, 2203 b, a keyboard 2204, an external connection port 2205, and apointing mouse 2206.

The notebook personal computer shown in FIG. 12(A), and FIG. 12(B)comprises the high-quality display portion 2203 a mainly for full-colordisplaying the images and the monochromatic display portion 2203 b fordisplaying mainly text and symbols.

Further, FIG. 12(C) is a perspective view of a mobile computer. FIG.12(D) is a perspective view showing the back surface side. The mobilecomputer comprises a body 2301. display portions 2302 a, 2302 b, aswitch 2303, a control key 2304, and an IR port 2305. It mainlycomprises the high-quality display portion 2302 a for full-colordisplaying images and the monochromatic display portion 2302 b fordisplaying mainly text and symbols.

Further, FIG. 12(E) shows a video camera comprising a body 2601, adisplay portion 2602, a case 2603, an external connection port 2604, aremote control socket 2605, an image pickup unit 2606, a battery 2606, avoice input unit 2608, and a control key 2609. The display portion 2602is a double-side light-emitting panel capable of high-quality displaymainly for full-color displaying the images on one surface andmonochromatically displaying mainly text and symbols on the othersurface. Further, the display portion 2602 can be rotated in themounting portion. The present invention can be employed in the displayportion 2602.

Further, FIG. 12(F) is a perspective view of a cellular phone. FIG.12(G) is a perspective view illustrating the folded state. The cellularphone comprises a body 2701, a case 2702, display portions 2703 a, 2703b, a voice input unit 2704, a voice output unit 2705, a control key2706, an external connection port 2707, and an antenna 2708.

The cellular phone shown in FIG. 12(F) and FIG. 12(G) comprises thehigh-quality display portion 2703 a mainly for full-color displaying theimages and the display portion 2703 b for displaying mainly text andsymbols by area colors. In this case, a color filter is used in thedisplay portion 2703 a, and an optical film serving as an area color isused for the display portion 2703 b.

Further, this example can be freely combined with Embodiments 1 to 4 andExamples 1 to 4.

Example 6

FIG. 16 is a drawing which illustrates charging of a cellular phoneusing the display device in accordance with the present invention. FIG.16 illustrates a state in which the cellular phone is opened and lightis emitted from both sides, but charging may be also conducted in aclosed state. In display devices using light-emitting elements, thelight-emitting elements generally deteriorate with time and luminositydecreases. In particular, in case of display devices in whichlight-emitting elements are disposed at a one-to-one ratio with pixels,because the frequency at which the pixels come on differs depending onthe location, the degree of deterioration also differs depending on thelocation. Therefore, in the pixels with a high switching frequency, thedegree of deterioration is high and image quality decreases as an imagepersistence effect. Accordingly, image persistence can be madeinconspicuous by conducting certain display during charging, which isnot a usual usage state, and switching on the pixels with a low usagefrequency. A full-screen operation mode, an image with brightnessinverted with respect to the standard image (stand-by screen and thelike), and an image displayed by detecting pixels with a low usagefrequency are examples of display contents during charging.

FIG. 14 is a block diagram corresponding to the drawing. A CPU 2001obtaining charging state detection signal from a charger 2017 issues acommand instructing a display controller 2004 to display a signalcorresponding to the above-described and a double-side light-emittingdisplay conducts light emission.

FIG. 15 illustrates an example of means for producing an image with abrightness inverted with respect to the standard image. The output of avideo signal selection switch 2106 is inputted into a switch 2107 and aselection can be made whether to input the signal of a switch 2106 intoa display 2101 as is or after inversion. When brightness inversion isnecessary, the input may be made after inversion. This selection isconducted with the display controller. Further, in a full-screenoperation mode, a fixed voltage may be inputted to the display 2101 (notshown in the figures).

The deterioration of displayed images can be thus inhibited byconducting light emission which decreases image persistence duringcharging.

Further, the present example can be freely combined with any ofEmbodiments 1 to 4 and Examples 1 to 5.

[Effect of the Invention]

With the present invention, a large mask with a high mask accuracy canbe realized for conducting selective deposition on a substrate with alarge surface area. Further, the present invention makes it possible torealize a deposition apparatus allowing a uniform film thickness to beobtained over the entire substrate surface even on substrates with alarge surface area.

1. A thin-sheet mask having a pattern opening, characterized in that themask is fixed to a frame in a stretched state and said mask isadhesively bonded in a location coinciding with a line passing through athermal expansion center in the members of the frame.
 2. The maskaccording to claim 1, characterized in that four corners of said framehave a curvature.
 3. The mask according to claim 1, characterized inthat said mask is adhesively bonded to the frame with an adhesivematerial having heat resistance.
 4. A thin-sheet mask having a patternopening, characterized in that the mask is fixed to a frame in astretched state and said mask is adhesively bonded in a location on theoutside of a line passing through a thermal expansion center in themembers of the frame, the frame is caused to expand by heating duringdeposition and the mask maintains the stretched state.
 5. The maskaccording to claim 4, characterized in that four corners of said framehave a curvature.
 6. The mask according to claim 4, characterized inthat said mask is adhesively bonded to the frame with an adhesivematerial having heat resistance.
 7. A container for accommodating adeposition material, which is disposed in a deposition source of adeposition apparatus, characterized in that the cross section in a planeof said container has a rectangular or square shape and the openingportion through which the deposition material passes has a thinelongated shape.
 8. A production apparatus comprising a loading chamber,a transportation chamber linked to said loading chamber, a plurality offilm forming chambers linked to said transportation chamber, and adisposition chamber linked to said film forming chambers, characterizedin that the plurality of film forming chambers comprise means for fixinga substrate which is linked to an evacuation chamber for evacuating theinside of the film forming chambers, a mask, a frame for fixing saidmask, alignment means for aligning the mask and the substrate, one ortwo deposition sources, means for moving said deposition sources insidesaid film forming chambers, and means for heating the substrate, and theend portion of the mask is adhesively bonded in a location matching aline passing through a thermal expansion center in the members of saidframe.
 9. The production apparatus according to claim 8, characterizedin that said film forming chambers and said disposition chamber comprisemeans capable of introducing a material gas or cleaning gas and linkedto the evacuation chamber for evacuating the inside of the chambers. 10.The production apparatus according to claim 8, characterized in thatsaid deposition source can be moved in the X direction, Y direction, orZ direction inside the film forming chamber.
 11. The productionapparatus according to claim 8, characterized in that a shutter forpartitioning the inside of the film forming chamber and shielding thedeposition on said substrate is provided in said film forming chamber.12. A production apparatus comprising a loading chamber, atransportation chamber linked to said loading chamber, a plurality offilm forming chambers linked to said transportation chamber, and adisposition chamber linked to said film forming chambers, characterizedin that the plurality of film forming chambers comprise means for fixinga substrate which is linked to an evacuation chamber for evacuating theinside of the film forming chambers, a mask, a frame for fixing saidmask, alignment means for aligning said mask and the substrate, one ortwo deposition sources, means for moving said deposition sources insidethe film forming chambers, and means for heating the substrate, and thecross section in a plane of the container for accommodating a depositionmaterial, which is disposed in said deposition source, has a rectangularor square shape and the opening portion has a thin elongated shape. 13.The production apparatus according to claim 12, characterized in thatsaid container is composed of an upper part and a lower part, andevaporation of the material from said deposition source is adjusted bythe shape of the opening portion in the upper part of the container. 14.The production apparatus according to claim 12, characterized in thatsaid film forming chambers and said disposition chamber comprise meanscapable of introducing a material gas or cleaning gas and linked to theevacuation chamber for evacuating the inside of the chambers.
 15. Theproduction apparatus according to claim 12, characterized in that saiddeposition source can be moved in the X direction, Y direction, or Zdirection inside the film forming chamber.
 16. The production apparatusaccording to claim 12, characterized in that a shutter for partitioningthe inside of the film forming chamber and shielding the deposition onsaid substrate is provided in said film forming chamber.